As a delivery driver of many years experience 99% of the time the problem lies with the customer who fail to have adequately clear signage as to where they live. OK, if they live in a communal building then it may be down to the management company / housing trust / etc which have failed to sign which of several blocks is which or which is the entrance to particular flat numbers but in that case the residents should be complaining to them to get it sorted rather than moan about delivery drivers left wondering which mole hill is which.
BTW putting a house number on the side of the house or on an open gate neither of which is visible from the road is not a clever idea. Nor is allowing that bush in the garden to overgrow the house sign.
Finally, delivery instructions which say it is the house with the blue car on the drive is not much good if the car is not there or it is a dark evening on an unlit village road. Nor instructions which say it is the third house in the left but which do not say which direction that is coming from.